I’m a couple days late on this — apologies for not following Terrelle Pryor on Twitter — but I’m also operating under the assumption that there are plenty of Broncos fans who aren’t exactly glued to the Raiders QB’s Twitter feed, either. Apologies if you’ve seen this already, but if not, here goes…

On Tuesday, Pryor tweeted three messages to his followers, messages that raised red flags for anyone concerned with concussions and safety issues in the NFL.

In a story that posted Wednesday morning on ESPN.com, Giants quarterback Eli Manning details to Ed Werder the trying experience that was Peyton Manning’s recovery from neck fusion surgery, which caused him to be cut by the Colts and question his future:

“I knew it would get better with time,” Eli Manning told ESPN. “But after several surgeries and you’re dealing with nerves — you didn’t know how quickly (he would recover). That was the scary thing for him — he didn’t know how quickly it would get better.”

Eli Manning recalled throwing with his older brother following the 2011 season, when Peyton missed the entire season and was released by the Indianapolis Colts. The youngest Manning said his older brother struggled to generate any velocity on his passes, a source of concern for both quarterbacks.

“It just wasn’t the same … it was frustrating and scary for him,” Eli Manning said. “He would look at me and say, ‘What looks wrong? Why is it coming out without any pop?'”

After the big three of Demaryius Thomas, Wes Welker and Eric Decker, the Broncos have had a fierce competition for the No. 4 and 5 receiver spots. Greg Orton made an early move but then suffered a severely sprained ankle.

Andre “Bubba” Caldwell had been the No. 4 receiver in recent weeks and fifth-round drafted rookie Tavarres King seemed to have the edge for No. 5.

But Gerell Robinson has been mixing in with the top offense in recent days. Robinson was a late cut by the Broncos as an undrafted rookie last season, then was signed to the Arizona Cardinals’ practice squad.

Another starter has suffered a significant injury. Broncos starting tight end Joel Dreessen had a setback in his recovery from kneecap surgery and will be out at least two weeks.

The Broncos’ top two tight ends from last year, Dreessen and Jacob Tamme, didn’t dress for the scrimmage Saturday. Tamme was sidelined last week with a pulled quad. They combined for 93 receptions in 2012.

With Dreessen and Tamme out, Julius Thomas started with the No. 1 offense Saturday. Virgil Green lined up with the No. 2 offense and made a terrific catch on an 18-yard throw from Brock osweiler. Jake O’Connell, a veteran signed a week ago, had a catch from No. 3 quarterback Zac Dysert.

Dreessen is the third starter to suffer a serious injury since training camp opened two weeks ago. Center Dan Koppen is done for the season with a torn ACL and right cornerback Dominique Rodgers-Cromartie will miss at least another week with a high ankle sprain.

With the season-ending injury to Broncos center Dan Koppen in Sunday’s practice, the team is now looking at a shallow pool of available replacements.

And in looking at the players available and how they’ve played in recent seasons, the best fits would likely be Steve Vallos and Eugene Amano. Amano has far more experience as a starter in the league — 68 starts and 124 games played in his career — but many personnel executives in the league say Amano is still looking for a multi-year contract befitting a starter rather than an unsigned free agent.

When the Broncos’ offseason training activities (OTAs) opened last month, Peyton Manning was asked how he felt physically this year compared to this time last year, when he was coming off a missed season and four neck surgeries. Manning basically blew off the question, saying nothing more than “I feel fine.”

Asked again Tuesday, Manning was ready to expand.

“I feel better,” he said.

“I’ve certainly made strides when you talk about in comparison to this time in 2012. Read more…

As Minnesota running back Adrian Peterson proved last season, ACL injuries aren’t what they used to be.

And so not quite 6 ½ months after Quenterus Smith had his torn left ACL repaired by Dr. James Andrews, the Broncos’ rookie defensive end was participating in individual and position drills the past two days.

“They told me to do what I can,’’ said Smith, a fifth-round draft pick out of Western Kentucky. “When I’m done doing the drills I feel good. I don’t feel all the way normal but I still have another month-and-a-half to get ready. They’re doing a great job with it with the little time we’ve had. But everything feels good. I don’t feel like I’m babysitting it too much.’’

Smith suffered the injury while passing rushing in a game on Nov. 17. Dr. Andrews repaired the tear on Nov. 24. The 6-foot-5 Smith plans on participating in the team portion of practices by the start of training camp in late-July.

INDIANAPOLIS — Broncos running back Knowshon Moreno has had arthroscopic surgery on his right knee since the end of the season. Broncos coach John Fox confirmed the surgery when asked Thursday morning at the NFL’s scouting combine.

Moreno underwent a treatment to insert stem cells harvested from bone marrow in his pelvis into his right knee. It is the same knee Moreno tore the anterior cruciate ligament (ACL) to end his 2011 season.

Moreno is currently rehabbing at the Broncos’ Dove Valley complex. The running back, who just finished his fourth year with the team, left the Broncos’ playoff loss to the Ravens with a knee injury.

Denver Broncos quarterback Peyton Manning said it was good to see guard Chris Kuper back on the practice field during Tuesday’s full-pad workout.

Kuper, a starter for the past six seasons, has missed nine games because of injuries, including knee and migraine-headache issues. This week he was named by the team for the Ed Block Courage Award, bestowed by each NFL team to a player that has overcome adversity.

Kuper played in the season finale against Kansas City but only on special teams.

Broncos right guard Chris Kuper is on the 46-man game day roster today but he won’t start against the Kansas City Chiefs. Manny Ramirez will get his 11th start at right guard.

Kuper has been out the past three games with a sprained left ankle and migraines. He will be able to knock off some rust on a couple special teams today but the plan is to not play him at guard until the playoffs.

Meanwhile, I just saw Broncos returner Trindon Holliday walk past the hallway outside the press box so he is officially out. Jim Leonhard will return punts and Omar Boldin will be the kickoff returner.

The Broncos have lost a few key players to injuries, including running back Willis McGahee, safety Quinton Carter, center J.D. Walton and linebacker Joe Mays. But Denver may be as healthy as any team at this stage of the season.

“This game’s about staying healthy, and injuries are part of this game every week,” Fox said Friday. “You deal with them. We’ve had the ‘next-man-up’ philosophy. We’ve got a lot of guys that have stepped in and done a terrific job, so good for them.

Broncos rookie running back Ronnie Hillman said he’s not nervous about getting more carries Sunday at Kansas City but acknowledged that he is “very excited” at the opportunity.

“Practice was different (this week), but it was cool,” Hillman said Friday before the Broncos departed for KC.

Even when getting some practice snaps with the starters, Hillman said he had to treat it as all business.

“I’m a young guy,” he said, “so I can’t afford to play around (in practice) like the older guys.”

The Broncos’ regular running back, Willis McGahee, is out six to eight weeks with an MCL sprain (right knee) and compression fracture. His roster spot was not filled this week, leaving Hillman, Lance Ball and Knowshon Moreno to replace him.

Hillman said the Broncos (7-3) expect the Chiefs (1-9) to give Denver their best shot. “Teams play tougher in division games,” Hillman said.

Running back Knowshon Moreno, the Broncos’ first selection in the 2009 draft, has been designated inactive for the past eight games. But that likely will end Sunday in the game at Kansas City.

On Monday, Broncos coach John Fox mentioned Moreno among the top candidates to replaced injured starter Willis McGahee, who tore the MCL in his right knee a day earlier against San Diego and could miss the remainder of the regular season and beyond.

Speaking to reporters Monday, Moreno showed a sense of humor when it was suggested that he should be fresh.

They are ranked 19th in the NFL with 105.3 yards per game. But they are No. 3 in total offense (394.2) and No. 2 in scoring (30.1). The primary purpose of the Broncos running game is to, first, give receivers Demaryius Thomas and Eric Decker a blow and let the offensive linemen attack instead of absorb. And secondly, set up Peyton Manning’s play-action passes.

Broncos medical staff tends to injured running back Willis McGahee in the first half against the Chargers. (Steve Nehf, The Denver Post)

Broncos running back Willis McGahee was having a nice game, gaining 55 yards on seven carries when he went down with a right knee injury early in the second quarter.

McGahee suffered a knee injury after he gained 8 yards with 13:33 remaining in the second quarter, a run that immediately preceded Peyton Manning’s 13-ayrd touchdown pass to Demaryius Thomas. McGahee did not return and will have an MRI on Monday to determine the full extent of the injury.

“It swelled up on him,” said Broncos coach John Fox. “We’ll know more (Monday).”

Ronnie Hillman and Lance Ball finished the game at tailback and combined for 78 yards rushing on 18 carries.

Speaking to reporters Friday following practice, Broncos linebacker Von Miller said the Denver defense can still be effective in pressuring Chargers quarterback Philip Rivers on Sunday without injured defensive end Elvis Dumervil.

Dumervil sprained a shoulder last weekend during the second quarter of the Broncos’ win at Carolina. He practiced Friday on a limited basis and his availability for Sunday’s game is listed as questionable.

Those unaware that Broncos cornerback Tracy Porter returned to the practice field Friday could guess that to be the case by his wide grin.

Porter participated on a limited basis and won’t play Sunday in the home game against San Diego. But this was a big step. He has been designated inactive for the past four games and hasn’t put on a uniform on game day since the Oct. 7 game at New England due to a recurrence of symptoms that preceded a seizure in August.

“It feels great to be back out there,” Porter said Friday after practice. “I’m still working my way back.

“But hopefully, next week I can hit the ground running and be ready next Sunday (for the Nov. 25 game at Kansas City).”

Mike Klis has been with The Denver Post since 1998, after working 13 years with the Colorado Springs Gazette Telegraph. Major League Baseball was Klis' initial passion. He started covering the Colorado Rockies after Coors Field was approved for construction in August 1990.

Nicki Jhabvala is the Sports Digital News Editor for The Denver Post. Before arriving in Denver, she spent five years at Sports Illustrated working primarily as its online NBA editor, and she was most recently the overnight home page editor at the New York Times. She has reported regularly on the Broncos since joining the staff.

A published author and award-winning journalist, Benjamin Hochman is a sports columnist for The Denver Post. He previously worked on the staff of the New Orleans Times-Picayune, winners of two Pulitzer Prizes for their Hurricane Katrina coverage.